Carpets were woven to order at Spain's Royal Tapestry Factory, linens were commissioned from Ireland and crockery and cutlery arrived from England.

The chosen site was once an area occupied by barracks belonging to the Hippodrome Circus and the gardens of the old Theatre Tivoli, and was formerly owned by Jardines del Buen Retiro de Madrid.

[5] The hotel's grand opening on 2 October 1910 was officiated by King Alfonso XIII in the company of ministers and representatives of the mayor of Madrid.

This was one of the first buildings in Madrid that used reinforced concrete in its construction, which was completed on 14 May 1910. Notable Spanish and foreign companies were hired to decorate the rooms.

Throughout its history, many famous guests have stayed at the hotel, from Ernest Hemingway to Rainier III, Prince of Monaco and his wife Grace Kelly who celebrated their honeymoon in one of its suites.

[18][citation needed], Jagatjit Singh and Anita Delgado,[19] Mata Hari,[19] Randolph Hearst and Marion Davies,[19] Haile Selassie.